This invention generally relates to the art of fiber optic circuitry and, particularly, to a fiber management system for a plurality of optical fibers from a fiber optic cable or circuit.
Fiber optic circuitry is increasingly being used in electronics systems where circuit density is ever-increasing and is difficult to provide with known electrically wired circuitry. An optical fiber circuit is formed by a plurality of optical fibers carried by a dielectric or substrate and the ends of the fibers are interconnected to various forms of connectors or other optical transmission devices. A fiber optic circuit may include a simple cable which includes a plurality of the optical fibers surrounded by an outer cladding or tubular dielectric. On the other hand, a more sophisticated optical backplane or flat fiber optic circuit is formed by a plurality of optical fibers mounted or routed on a substrate in a given pattern or circuit geometry. Optical backplanes are used to interconnect optical circuit components which transmit signals optically, as well as electrical circuit components, wiring boards, modules and/or integrated circuits. When an optical backplane interconnects electrical components, the electrical energy of each component is translated to optical energy which is transmitted by optical fibers on the optical backplane to another electrical component where it is translated back to electrical energy for transmission to the other electrical component. Optical fibers can transmit much more information than electrical conductors and with significantly less signal degradation.
In any such configurations, whether the fiber optic circuit is a simple round cable, a flat flexible circuit or an optical backplane, the individual optical fibers often extend beyond an edge or end of the dielectric or substrate whereby the individual fibers can be manipulated during termination of the fibers to various connectors or other fiber optic transmission devices. These loose fiber ends must be managed in some manner to prevent their breakage and/or entanglement. Heretofore, the fiber ends which extend away from the supporting dielectric or substrate have been attached together in a ribbon format and eventually xe2x80x9cbroken outxe2x80x9d (separated into individual fibers) at some other location using a breakout kit. Such breakout kits have numerous disadvantages, including the fact that the kits are fairly sizable and are too large for some applications. The breakout kits also are heavy and may pull on the optical fibers if the kit is not properly supported. Still further, such breakout kits are extraneous devices that must be purchased and this significantly increases the cost of the ultimate fiber optic circuitry.
The present invention is directed to solving these various problems by providing a simple fiber management assembly which is lightweight and is attached directly to the fiber optic circuit to protect the loose fiber ends and to allow for easy manipulation and termination of the fibers.
An object, therefore, of the invention is to provide a new and improved fiber management system for a plurality of optical fibers which project beyond an edge or end of a dielectric or substrate of a fiber optic circuit, such as a flat fiber optic circuit.
In the exemplary embodiment of the invention, the system includes a support secured to the dielectric or substrate of the circuit at an edge or end thereof. A plurality of tubes are fixed to the support and extend away from the substrate. The fibers are positioned within the tubes so that the fibers are protected and are easily manipulated for terminating the fibers to connectors or other fiber optic transmission devices.
As disclosed herein, the support is fabricated of generally rigid dielectric material such as plastic or the like. The support is elongated and is secured to the substrate at opposite ends of the support outside an array of the optical fibers on the substrate. The support includes a pair of mounting posts at the opposite ends thereof, and the mounting posts extend through a pair of mounting holes in the substrate of the circuit. Locking means, such as lock washers, are engageable with the mounting posts to secure the support to the substrate. Preferably, the support is secured to the substrate substantially within a cutout in an edge of the substrate, whereby the support is located totally within the profile of the substrate.
In the preferred embodiment, the tubes which encase the fibers are flexible and are fabricated of such material as a polymer. The tubes are oversized relative to the fibers so that the fibers are loose within the tubes and can move relative to the tubes due to a differential thermal expansion and contraction between the fibers and the tubes. Providing relative movement between sections of the fibers and the substrate immediately adjacent the support also facilitates this differential in thermal expansion and contraction. The fibers may extend slightly beyond the ends of the tubes for termination to appropriate connecting devices, or the ends of the tubes may be cut-off to expose the fiber ends for termination.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.